Fasteners are important during any construction project because they help to anchor something, such as an air conditioning unit, into a base (concrete floor, for example). This article discusses the two common kinds of fasteners that you can use during your project. Use this information to select the best fastener for your needs. Mechanical Fasteners Mechanical fasteners depend on friction to stay firmly anchored in the base. The installation process starts with drilling a hole of the appropriate diameter within a substrate or base.